Since liquid crystals cannot emit light by themselves, a backlight module is used as a light source for providing uniform brightness to the liquid crystal panel in a liquid crystal display. In generally, the backlight module converts a typical point light source or linear light source into a surface light source with a high brightness and a uniform brilliance through a series of optical sheets, so that the display panel can display images normally.
Generally, the backlight module mainly includes a light source, a reflector, a light guide plate, a frame and the like. In the prior art, the light source includes a cold cathode fluorescent lamp (CCFL) or a LED (light emitting diode), light beams emitted from these light sources are generally dispersed after being guided by the light guide plate, the focusing effect is poor, it is necessary to adopt an additional prism sheet to focus the dispersed light beams, so as to improve focusing effect, thus the brightness of the backlight module can be increased. In addition, these light sources have defects such as narrow color gamut and low efficiency.
Hence, it has become a problem to be solved urgently at present to realize high focusing effect, wide color gamut and high efficiency of the backlight module.